Issy thanks but fuses checked and OK

Charger output listed as 19v @ 3.42amps

Found an old Sony Charger output listed as 19.5 v @ 4.7amps decided not to use it so will look for new charger locally tomorrow.

Have you checked yours with the multimeter? Edit: (sorry, missed your post saying you had), below still stands though.

The Sony one almost certainly a different plug, but you really need to find out why your laptop appears to have blown up 2 chargers, or it'll probably instantly blow up a 3rd.

If you don't know what you're doing (and I freely admit I don't know what to suggest, that's a very odd problem) may I politely suggest you give it to someone who does, better than throwing money at chargers.

Thanks for all the advice guys, both chargers appear to have been fried by the fault on my laptop

New charger received last night.

Battery removed from wife's laptop, new charger connected and laptop springs into life when switched on.

Battery refitted and it starts to charge, reaches 100% after about half an hour.

Not sure about using charger with my laptop in case fault still present and new charger gets fried. I suspect broken hinge above input socket may be cause of original problem.
Ray